Tuesday, June 19, 2012

June 20th, 2012 Forecast

People around the region are enjoying the last bit of relatively comfortable weather, as the broiler gets turned up in time for tomorrow.  Yesterday, under mostly cloudy skies, temperatures stuck in the upper 60's to lower 70's.  On Tuesday, Temperatures ventured closer to the 80-degree mark with noticeably more humidity and with lingering cloudiness.  High pressure will move to our south, setting up a classic "Bermuda High", where winds around the high pick up warm and moist air from the south and push that air mass to the north.  It's also important to mention that there is an Excessive Heat Warning for Philadelphia and the surrounding counties for Wednesday and into Thursday.  Heat Index values could reach up to 110-degrees with the heat and humidity combined.

Tonight might be the last of the pleasant nights to get out and enjoy before the humidity really gets turned up.  Partly cloudy skies and lows near the 70-degree mark are on tap, except far north and west of the city, where a few showers and a rumble of thunder or two can be expected.  Winds from the southwest act as a heat pump bringing in the warm, tropical air.  Tomorrow starts day one of the potential heat wave.  Highs in the mid to upper 90's here in the city and south and east and lower 90's north and west.  Winds from the west, at 5 to 10 mph.

Thursday marks day two, with temperatures in the upper 90's around the metro, with some places topping the century mark as you head further south.  Not a lot of relief overnight Wednesday and Thursday as lows will be in the mid-70's.  These lows are warmer than some of our highs in the past week.  The humidity sticks around on Thursday as well.  Friday could potentially mark day three of our 90-degree temperatures, making this an official heat wave.  Some afternoon and evening precipitation could provide some relief as the air mass starts to change.  Saturday is the best day of the extended forecast.  Lower humidity and lower temperatures make it at least bearable to stay outside for an extended period of time.

Sunday, more showers and thunderstorms are forecasted, however skies will mostly be on the partly cloudy range.  Temperatures still in the upper 80's however, any breeze will have a more cooling effect than earlier in the week.  Another system starts to move in for the beginning of the work week.  Monday, a majority of the day will feature clouds and sun, however clouds will start to thicken towards night fall.  Tuesday, temperatures will be cooler, with overcast skies and scattered showers.

For safety information on the heat, check out this National Weather Service page here.